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Remember the Rainforest 1

 

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---continuation commentary #9e----

Finally it must not be forgotten in this matter that trees of such vast antiquity could have passed through even several periods in which they might add at one time wider rings of growth, and at another narrower rings. And from these things it will be clear that we do not have, unless the number of rings of annual growth has been observed, any certain way of determining the age of the trees about which we are speaking, beyond comparing together the width of the rings that different trees of that region display and determining the age from that. Now when I have disclosed that the annual rings vary between 1 lin., 1/2 lin., 1/3 lin., and 1/4 lin., we might calculate that the wooden body of the tree grew by an average of 1/2 lin. every year, and since the half diameter has been set at 1368 lin., from there results an age of 2736 years. 

If this calculation were to seem acceptable, then this tree would be contemporary with the lifetime of Homer and would have already passed its three hundred and thirty-second year when Pythagoras was in his prime (584 BC). But if we were to set the rings of annual growth at an average thickness of 2/3 lin., then we would have 2052 years; if at 1/3 lin., then straightway a doubling of the age would result, giving the very great number of 4104 years. 

Etching 9 Ancient trees from Martius's Flora Brasiliensis 1840. Thanks to Lehigh U., Special Collections ! Color by C. Miranda Chor

Now as for the quantity of wood that is in this giant tree, that will be able to be determined accurately only when the length and thickness of the trunk and of the larger and smaller branches has been ascertained, which circumstances did not permit me. But if we posit, according to the overall appearance, that the cylinder of the tree up to the first branch was 70 feet long and 16 to 17 feet thick in the middle of this stretch, then it could be Robinia pseudoacacia, unknown photographer.calculated that the trunk alone contained 15,000 cubic feet of wood; nor does it seem improbable that all the larger and smaller branches together with the trunk amounted to 25,000 cubic feet of wood. The specific gravity of the well-dried wood of two kinds from the order of the Leguminosae, in which I suspect this tree is to be placed, was equal to 1.044 and 1.260, to judge from those that have been examined; but if the wood was green and plentifully full of juices, then it is surely to be thought to have a specific gravity of 1.35, comparable to other dense kinds of wood such as that of Robinia Pseudoacacia, which even dry, has a specific gravity of 0.904; from which it follows that 25,000 cubic feet of this wood is 35 percent heavier than the same amount of water, which weighs 2,400,000 pounds.

Etching commentary #9e